Shortest Path Bridging IEEE 802 - NANOG
42
Shortest Path Bridging IEEE 802.1aq NANOG49 June 13-16/2010 Peter Ashwood-Smith Fellow [email protected]
Transcript of Shortest Path Bridging IEEE 802 - NANOG
NANOG49 June 13-16/2010
Peter Ashwood-Smith Fellow
[email protected]
2
Abstract
802.1aq Shortest Path Bridging is being standardized by the IEEE as an evolution of the various spanning tree protocols. 802.1aq allows for true shortest path routing, multiple equal cost paths, much larger layer 2 topologies, faster convergence, vastly improved use of the mesh topology, single point provisioning for logical membership (E-LINE/E-LAN/E-TREE etc), abstraction of attached device MAC addresses from the transit devices, head end and/or transit multicast replication , all while supporting the full suit of 802.1 OA&M.
3
Outline
• Challenges • What is 802.1aq/SPB • Applications • How does it work • Example (won’t cover but included here)
4
Challenges • L2 networks that scale to ~1000 bridges. • Use of arbitrary mesh topologies. • Use of (multiple) shortest paths. • Efficient broadcast/multicast routing and replication points. • Avoid address learning by tandem devices. • Get recovery times into 100’s of millisecond range for larger
topologies. • Good scaling without loops. • Allow creation of very many logical L2 topologies (subnets)
of arbitrary span. • Maintain all L2 properties within the logical L2 topologies
(transparency, ordering, symmetry, congruence, shortest path etc).
• Reuse all existing Ethernet OA&M 802.1ag/Y.1731
5
A1.. A100
7
What is 802.1aq/SPB • IEEE protocol builds on 802.1 standards • A new control plane for Q-in-Q and M-in-M
– Leverage existing inexpensive ASICs – Q-in-Q mode called SPBV – M-in-M mode called SPBM
• Backward compatible to 802.1 – 802.1ag, Y.1731, Data Center Bridging suite
• Multiple loop free shortest paths routing – Excellent use of mesh connectivity – Currently 16, path to 1000’s including hashed per
hop. • Optimum multicast
8
What is 802.1aq/SPB (cont’d) • Light weight form of traffic engineering
– Head end assignment of traffic to 16 shortest paths. – Deterministic routing - offline tools predict exact routes.
• Scales to ~1000 or so devices – Uses IS-IS already proven well beyond 1000. – Huge improvement over the STP scales.
• Good convergence with minimal fuss – sub second (modern processor, well designed) – below 100ms (use of hardware multicast for updates) – Includes multicast flow when replication point dies.
Pre-standard seeing 300ms recovery @ ~50 nodes. • IS-IS
– Operate as independent IS-IS instance, or within IS-IS/ IP, supports Multi Topology to allow multiple instances efficiently.
9
What is 802.1aq/SPB (cont’d) • Membership advertised in same protocol as
topology. – Minimizes complexity, near plug-and-play – Support E-LINE/E-LAN/E-TREE – All just variations on membership attributes.
• Address learning restricted to edge (M-in-M) – FDB is computed and populated just like a router. – Unicast and Multicast handled at same time. – Nodal or Card/Port addressing for dual homing.
• Computations guarantee ucast/mcast… – Symmetry (same in both directions) – Congruence (unicast/multicast follow same route) – Tune-ability (currently 16 equal costs paths – opaque
allows more)
All links usable
12
Application (M|R)STP replacement
• Many more nodes without regions • Low effort to get good routing • Fast convergence – link state v.s. distance vec • Address isolation m-in-m.
R
Unused links
for scale
• Virtualization operates in subnet. • Fully compatible with all 802.1
Data Center Bridging protocols & OA&M.
• Address isolation through m-in-m
• Fast recovery • No loops
Application Data Center (cont’d)
• Totally compatible with Vmware server functions: • OA&M, motion, backup etc. • Apps that sit on Vmware ‘just work’.
• Totally compatible with Microsoft load balancing (multicast over the L2)
• VRRP transparent. • It just makes the L2 part of the DC larger
and better utilized. • Compatible with emerging Inter DC overlay
work.
15
Application Metro/L2VPN • Very light weight L2VPNs (2^24 data path) of:
E-LAN, E-LINE, E-TREE flavors (a very cheap VPLS) • Can do VPLS style head end replication • Can do p2mp style transit replication (just one tx flag). • Can support receive only membership (E-TREE)
- E-LINE = 2 tx/rx members
- E-LAN > 2 tx/rx members
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Outline
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- Plug NNI’s together - Group ports/c-vlan/s-vlan at UNIs that you
want to bridge (224 groups=‘services’ m-in-m mode.)
- Assign an I-SID to each group..
• Internally - IS-IS reads box MAC, forms NNI adjacencies - IS-IS advertises box MACs (so no config). - IS-IS reads UNI port services and advertises. - Computations produce FIBs that bridge service
members.
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Data Path (M-in-M mode) • C-vlan/S-vlan or untagged traffic arrives at UNI • Its encapsulated with B-SA of bridge • Its encapsulated with I-SID configured for group • Its encapsulated with B-VID chosen for route • C-DA is looked up, if found B-DA is set • C-DA not found, B-DA is multicast that says:
• Multicast to all other members of this I-SID group from ‘me’. Or can head-end replicate over unicast.
• C addresses to B address association learned at UNI only.
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FDB (unicast M-in-M mode)
• A unique shortest path from node to all others is computed.
• BMAC of other nodes installed in FIB pointing to appropriate out interface.
• Above is repeated for 16+ shortest paths each causes a different B-VID to be used.
• Symmetry is assured through special tie- breaking logic. 16+ different tie-breaking algorithms permit 16+ different shortest paths.
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:1
3 6
MAC | BVID | IF :4 | 1 | 9 :4 | 2 | 9 :4 | 3 | 10 :4 | 4 | 10
MAC | BVID | IF :1 | 1 | 3 :1 | 2 | 6 :1 | 3 | 3 :1 | 4 | 6
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FDB (mcast M-in-M mode) If no services require tandem replication there is no tandem FDB:
Very VPLS like .. Pretty boring….head replication over unicast paths .. Yawn..
Else (mp2mp like but without signaling) If my node is on a unique shortest path
between node A , which transmits for a group I, and node B which receives on group I, then: merge into the FDB an entry for traffic from { A/Group I } to the interface towards B.
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How does it work – transit multicast format (n/a for head replication)
Example: { SOURCE: 0A-BC-DE / ISID: fe-dc-ba }
MMAC-DA: A3-BC-DE-FE-DC-BA 0011
:1
I=255
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Highlighted is the routing from each member to all others.
Note the symmetry.
Unicast and multicast Follows exactly these Routes.
Multicast can be replicated at fork points or head end replicated to the uni-cast paths by configuration at edge.
ANIMATION FOR E-LAN ‘100’ WITH 7 MEMBERS
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The Control Plane (m-in-m mode) • Industry standard IS-IS Link State Protocol is
basis for 802.1aq. • Does not require any IP to operate. • Does not preclude IPV4 or IPV6 being present in
same IS-IS instance. • SYSID carries B-MAC address • Introduces no new PDU’s to IS-IS. • Hello TLVs augmented to pass Equal Cost
Algorithm / Vid information and new NLPID. • Update TLV’s augmented to advertise SPB
specific link costs. • Update TLVs augmented to advertise ISID
information. • Update TLVs augmented to advertise nodal ‘short
form’ name SPSOURCEID (transit mcast only).
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802.1aq ISIS LSP extensions at a glance LSPID Seq Num Checksum …. ----------------------------------------------
4455.6677.0001.00-00 0x0000007a 0xc01f ….. SOURCE 4455.6677.0001.00 HOST NAME Instance_1 NLPID SPB (0xC1) AREA ADDR 22.3344 NBR ID 4455.6677.0004.00 COST: 10 NBR ID 4455.6677.0003.00 COST: 10 SPSOURCEID 07-00-01 SPB ECT-ALGORITHM 1 ECT-VID 101 SPB ECT-ALGORITHM 0 ECT-VID 100
SPB BMAC 44-55-66-77-00-01 ECT-VID 100 SPB ISID 255T&R SPB BMAC 44-55-66-77-00-01 ECT-VID 101 SPB ISID 256T&R
10
10
255
:4
:3
LSP fragment for node :1 with 2 peers :4 and :3 and two services 255, 256
(1)
(2)
(4)
(3)
(5)
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Loop Suppression & Avoidance Suppression
• done on the data path using an SA check. • prevents 99.99% loops if FDB’s create one. • no impact on convergence rates. • exploits symmetric/congruence properties of routing. • uses reverse learning options of most h/w to discard.
Avoidance • done by the control path • ensures no loops are ever configured in FDBs. • hellos augmented with topology ‘digests’ • mismatched digests => some forwarding entries unsafe. • blocks only ‘unsafe’ entries. • works for ALL forwarding modes current and planned.
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802.1aq OA&M (inherited by design) Service/Network Layer – 802.1ag Connectivity Fault mgmt
•Hierarchy (honors maintenance levels/abstraction) •Continuity Check •L2 traceroute •L2 ping
Link Layer – 802.3ah •Link Monitoring (logical/physical) •Remote Failure Indication •Remote Loopback
Service Layer - Y.1731 •Multicast Loopback – depends on congruency/symmetry •Performance Measurements (Loss/Delay etc.) •One way/two way delays – symmetry important
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Recovery • ISIS augmented with multicast LSP flood to all 802.1aq
nodes. • Every 802.1aq node joins default service ISID 0xffffff. • This E-LAN is just for control plane. • LSPs can be advertised over this E-LAN • Very fast distribution protocol (h/w multicast). • On failure each end of link advertises over
this ‘default’ E-LAN (in addition to normal updates). • Reaches all 802.1aq participants at h/w multicast speed
with no CPU involvement transit. • Conceptually like having a shared LAN joining all nodes
with a physical port but no DR election etc. is done, only used as unreliable very fast distribution mechanism backed up by normal IS-IS hop by hop LSPs.
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Outline
• Challenges • What is 802.1aq/SPB • Applications • How does it work • Example (included in this deck - enjoy) • Q&A
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Outline
• Challenges • What is 802.1aq/SPB • Applications • How does it work • Example (backup slides) • Q&A (avail anytime)
AQ
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“Shortest Path Bridging – Efficient Control of Larger Ethernet Networks” : upcomming IEEE Communications Magazine – Oct 2010
“Provider Link State Bridging” : IEEE Communications Magazine V46/N9– Sept 2008 http://locuhome.com/wp-content/uploads/2009/02/ ieeecommunicationsmagazinevol46no9sep2008-carrierscaleethernet.pdf
See also the worked example – in backup slides in this deck
References
Thank-You
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EXAMPLE
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Full Transit Replication
EXAMPLE – ISIS PEERS AT NODE :3
<ottawa-9300-3>d spb The current global spb information is : Device HMAC is 44-55-66-77-00-03 Spsid is 07-00-03 Ect vlan amount is 2 Ect vlan sequence number [1] is: vlan 100 ! Ect vlan sequence number [2] is: vlan 101 ! <ottawa-9300-3>
<ottawa-9300-3>d isis peer
Peer information for ISIS(1) ---------------------------- System Id Interface Circuit Id State HoldTime Type 4455.6677.0001 Vlanif211 0000000002 Up 26s L1 4455.6677.0004 Vlanif212 0000000003 Up 23s L1 4455.6677.0005 Vlanif216 004 Up 27s L1 4455.6677.0015 Vlanif217 005 Up 27s L1 4455.6677.0017 Vlanif218 006 Up 25s L1 Total Peer(s): 5
<ottawa-9300-3>
Logging on to node :3 We can see the basic SPB info and the ISIS peers….
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EXAMPLE – LSDB at node :3 Database information for ISIS(1) -------------------------------- Level-1 Link State Database LSPID Seq Num Checksum Holdtime Length ATT/P/OL ------------------------------------------------------------------------------- 4455.6677.0001.00-00 0x00000fd2 0x1cea 1044 236 0/0/0 4455.6677.0003.00-00* 0x00001448 0x3d27 683 323 0/0/0 4455.6677.0004.00-00 0x00000ff8 0xd1d9 1090 323 0/0/0 4455.6677.0005.00-00 0x00000b3b 0x9ba7 586 317 0/0/0 4455.6677.0006.00-00 0x00000b3b 0xbc31 819 293 0/0/0 4455.6677.0007.00-00 0x00000b3b 0xce10 1075 293 0/0/0 4455.6677.0008.00-00 0x00000b3e 0xebe0 288 293 0/0/0 4455.6677.0009.00-00 0x00000b3b 0x8b77 355 317 0/0/0 4455.6677.000a.00-00 0x00000b3b 0x57a 840 294 0/0/0 4455.6677.000b.00-00 0x00000b3a 0x1665 608 294 0/0/0 4455.6677.000c.00-00 0x00000b3a 0x6903 764 294 0/0/0 4455.6677.000d.00-00 0x00000b3a 0x89fd 431 294 0/0/0 4455.6677.000e.00-00 0x00000b39 0x3445 611 294 0/0/0 4455.6677.000f.00-00 0x00000b3a 0xdabe 616 294 0/0/0 4455.6677.0010.00-00 0x00000b3b 0x810e 452 294 0/0/0 4455.6677.0011.00-00 0x00000b3a 0x1b46 645 294 0/0/0 4455.6677.0012.00-00 0x00000b39 0x1b3e 447 294 0/0/0 4455.6677.0013.00-00 0x00000b3a 0x943a 419 176 0/0/0 4455.6677.0014.00-00 0x00000b3b 0xdff2 693 176 0/0/0 4455.6677.0015.00-00 0x00000b41 0xdade 1141 508 0/0/0 4455.6677.0016.00-00 0x00000b3e 0xa832 1011 464 0/0/0 4455.6677.0017.00-00 0x00000b40 0x1563 640 508 0/0/0 4455.6677.0018.00-00 0x00000b3a 0xadee 417 464 0/0/0 4455.6677.0019.00-00 0x00000b3a 0xcff 291 158 0/0/0 4455.6677.001a.00-00 0x00000b3b 0xb131 794 176 0/0/0 4455.6677.001b.00-00 0x00000b3b 0x7062 822 176 0/0/0 4455.6677.001c.00-00 0x00000b3b 0x5876 463 176 0/0/0 4455.6677.001d.00-00 0x00000b3b 0xa610 460 176 0/0/0 4455.6677.001e.00-00 0x00000b3a 0xf5c6 627 176 0/0/0 4455.6677.001f.00-00 0x00000b3b 0x8a19 825 176 0/0/0 4455.6677.0020.00-00 0x00000b3a 0x960a 584 176 0/0/0 4455.6677.0021.00-00 0x00000b3b 0x5b58 1033 176 0/0/0 4455.6677.0022.00-00 0x00000b3a 0x8927 693 176 0/0/0 4455.6677.0023.00-00 0x00000b3b 0x9352 664 158 0/0/0 4455.6677.0024.00-00 0x00000b39 0xc8ec 736 176 0/0/0
*(In TLV)-Leaking Route, *(By LSPID)-Self LSP, +-Self LSP(Extended), ATT-Attached, P-Partition, OL-Overload
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<ottawa-9300-3>d isis lsdb 4455.6677.0001.00-00 verbose
Database information for ISIS(1) --------------------------------
Level-1 Link State Database
LSPID Seq Num Checksum Holdtime -------------------------------------------------------------
4455.6677.0001.00-00 0x00000fd3 0x1aeb 1194 SOURCE 4455.6677.0001.00 NLPID SPB(0xC1) AREA ADDR 22.3344 +NBR ID 4455.6677.0003.00 COST: 10 +NBR ID 4455.6677.0004.00 COST: 10 SPB ECT-ALGORITHM 0 ECT-VID 100 SPB ECT-ALGORITHM 1 ECT-VID 101 SPB ECT-ALGORITHM 2 ECT-VID 0 ……. SPB ECT-ALGORITHM 15 ECT-VID 0 SPSID 07-00-01 SPB BMAC 44-55-66-77-00-01 ECT-VID 100 SPB ISID 255T&R
<ottawa-9300-3>
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EXAMPLE – NODE :3 ROUTE TO :10 (first equal cost path)
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EXAMPLE – NODE :3 ROUTE TO :10 (second equal cost path)
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EXAMPLE: E-LAN MCAST ROUTES FROM :1 (left) and :26 (right)
Here are the multicast routes from node 1 for service 255 and also from node 26 for service 255. Note the symmetry in the route between the two multicast trees. The unicast route between :1 and :26 is also along that same path for the chosen B-VID. Since we’ve asked for transit replication for all members of the E-LAN we install MCAST …
SRC
SRC
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EXAMPLE: E-LAN MCAST ROUTES FROM :1 (left) and :26 (right)
<ottawa-9300-3>d spb mmac --------------------------------------------------------------- IN_PORT VID BMAC OUT_PORT --------------------------------------------------------------- ... GE2/0/11 100 7300-0100-00ff GE2/0/16, GE2/0/10 ... Total multicast num is 7 <ottawa-9300-3>
+-----+-------+-------------------+------+--------------- | FLG | IN/IF | DESTINATION ADDR | BVID | OUT/IF(s) +-----+-------+-------------------+------+--------------- | | if/01 | 7300-0100-00ff | 0100 | {if/5,if/6 } ….
5
MULTICAST ADDRESS IS: [ SOURCE = 07-00-01 | ISID=00-00-ff ]
We only get this state if we configure transmit membership in the E-LAN. Transmit still possible without multicast state but uses serial replication at head end. Operator chooses trade-off between state/bandwidth usage.
1
42
Here are all mFIBs on nodes :3 and :13 related to this E-LAN.
<ottawa-9300-3>d spb mmac --------------------------------------------------------------- IN_PORT VID BMAC OUT_PORT --------------------------------------------------------------- GE2/0/16 100 0300-1300-00ff GE2/0/10, GE2/0/11 GE2/0/16 100 0300-1400-00ff GE2/0/10, GE2/0/11 GE2/0/16 100 0300-1a00-00ff GE2/0/10, GE2/0/11 GE2/0/16 100 0300-1d00-00ff GE2/0/10, GE2/0/11 GE2/0/16 100 0300-1e00-00ff GE2/0/10, GE2/0/11 GE2/0/11 100 7300-0100-00ff GE2/0/16, GE2/0/10 GE2/0/10 100 7300-0200-00ff GE2/0/16, GE2/0/11 Total multicast num is 7 <ottawa-9300-3>
+-----+-------+-------------------+------+--------------- | FLG | IN/IF | DESTINATION ADDR | BVID | OUT/IF(s) +-----+-------+-------------------+------+--------------- | | if/01 | 7300-0100-00ff | 0100 | {if/5,if/6 } | | if/01 | 7300-0200-00ff | 0100 | {if/5,if/6 } | | if/01 | 0300-1a00-00ff | 0100 | {if/5,if/6 } | | if/05 | 0300-1d00-00ff | 0100 | {if/1,if/3,if/6 } | | if/06 | 0300-1e00-00ff | 0100 | {if/1,if/3,if/5 } | | if/03 | 0300-2400-00ff | 0100 | {if/5,if/6 }
Peter Ashwood-Smith Fellow
[email protected]
2
Abstract
802.1aq Shortest Path Bridging is being standardized by the IEEE as an evolution of the various spanning tree protocols. 802.1aq allows for true shortest path routing, multiple equal cost paths, much larger layer 2 topologies, faster convergence, vastly improved use of the mesh topology, single point provisioning for logical membership (E-LINE/E-LAN/E-TREE etc), abstraction of attached device MAC addresses from the transit devices, head end and/or transit multicast replication , all while supporting the full suit of 802.1 OA&M.
3
Outline
• Challenges • What is 802.1aq/SPB • Applications • How does it work • Example (won’t cover but included here)
4
Challenges • L2 networks that scale to ~1000 bridges. • Use of arbitrary mesh topologies. • Use of (multiple) shortest paths. • Efficient broadcast/multicast routing and replication points. • Avoid address learning by tandem devices. • Get recovery times into 100’s of millisecond range for larger
topologies. • Good scaling without loops. • Allow creation of very many logical L2 topologies (subnets)
of arbitrary span. • Maintain all L2 properties within the logical L2 topologies
(transparency, ordering, symmetry, congruence, shortest path etc).
• Reuse all existing Ethernet OA&M 802.1ag/Y.1731
5
A1.. A100
7
What is 802.1aq/SPB • IEEE protocol builds on 802.1 standards • A new control plane for Q-in-Q and M-in-M
– Leverage existing inexpensive ASICs – Q-in-Q mode called SPBV – M-in-M mode called SPBM
• Backward compatible to 802.1 – 802.1ag, Y.1731, Data Center Bridging suite
• Multiple loop free shortest paths routing – Excellent use of mesh connectivity – Currently 16, path to 1000’s including hashed per
hop. • Optimum multicast
8
What is 802.1aq/SPB (cont’d) • Light weight form of traffic engineering
– Head end assignment of traffic to 16 shortest paths. – Deterministic routing - offline tools predict exact routes.
• Scales to ~1000 or so devices – Uses IS-IS already proven well beyond 1000. – Huge improvement over the STP scales.
• Good convergence with minimal fuss – sub second (modern processor, well designed) – below 100ms (use of hardware multicast for updates) – Includes multicast flow when replication point dies.
Pre-standard seeing 300ms recovery @ ~50 nodes. • IS-IS
– Operate as independent IS-IS instance, or within IS-IS/ IP, supports Multi Topology to allow multiple instances efficiently.
9
What is 802.1aq/SPB (cont’d) • Membership advertised in same protocol as
topology. – Minimizes complexity, near plug-and-play – Support E-LINE/E-LAN/E-TREE – All just variations on membership attributes.
• Address learning restricted to edge (M-in-M) – FDB is computed and populated just like a router. – Unicast and Multicast handled at same time. – Nodal or Card/Port addressing for dual homing.
• Computations guarantee ucast/mcast… – Symmetry (same in both directions) – Congruence (unicast/multicast follow same route) – Tune-ability (currently 16 equal costs paths – opaque
allows more)
All links usable
12
Application (M|R)STP replacement
• Many more nodes without regions • Low effort to get good routing • Fast convergence – link state v.s. distance vec • Address isolation m-in-m.
R
Unused links
for scale
• Virtualization operates in subnet. • Fully compatible with all 802.1
Data Center Bridging protocols & OA&M.
• Address isolation through m-in-m
• Fast recovery • No loops
Application Data Center (cont’d)
• Totally compatible with Vmware server functions: • OA&M, motion, backup etc. • Apps that sit on Vmware ‘just work’.
• Totally compatible with Microsoft load balancing (multicast over the L2)
• VRRP transparent. • It just makes the L2 part of the DC larger
and better utilized. • Compatible with emerging Inter DC overlay
work.
15
Application Metro/L2VPN • Very light weight L2VPNs (2^24 data path) of:
E-LAN, E-LINE, E-TREE flavors (a very cheap VPLS) • Can do VPLS style head end replication • Can do p2mp style transit replication (just one tx flag). • Can support receive only membership (E-TREE)
- E-LINE = 2 tx/rx members
- E-LAN > 2 tx/rx members
16
Outline
17
- Plug NNI’s together - Group ports/c-vlan/s-vlan at UNIs that you
want to bridge (224 groups=‘services’ m-in-m mode.)
- Assign an I-SID to each group..
• Internally - IS-IS reads box MAC, forms NNI adjacencies - IS-IS advertises box MACs (so no config). - IS-IS reads UNI port services and advertises. - Computations produce FIBs that bridge service
members.
18
Data Path (M-in-M mode) • C-vlan/S-vlan or untagged traffic arrives at UNI • Its encapsulated with B-SA of bridge • Its encapsulated with I-SID configured for group • Its encapsulated with B-VID chosen for route • C-DA is looked up, if found B-DA is set • C-DA not found, B-DA is multicast that says:
• Multicast to all other members of this I-SID group from ‘me’. Or can head-end replicate over unicast.
• C addresses to B address association learned at UNI only.
19
FDB (unicast M-in-M mode)
• A unique shortest path from node to all others is computed.
• BMAC of other nodes installed in FIB pointing to appropriate out interface.
• Above is repeated for 16+ shortest paths each causes a different B-VID to be used.
• Symmetry is assured through special tie- breaking logic. 16+ different tie-breaking algorithms permit 16+ different shortest paths.
20
:1
3 6
MAC | BVID | IF :4 | 1 | 9 :4 | 2 | 9 :4 | 3 | 10 :4 | 4 | 10
MAC | BVID | IF :1 | 1 | 3 :1 | 2 | 6 :1 | 3 | 3 :1 | 4 | 6
21
FDB (mcast M-in-M mode) If no services require tandem replication there is no tandem FDB:
Very VPLS like .. Pretty boring….head replication over unicast paths .. Yawn..
Else (mp2mp like but without signaling) If my node is on a unique shortest path
between node A , which transmits for a group I, and node B which receives on group I, then: merge into the FDB an entry for traffic from { A/Group I } to the interface towards B.
22
How does it work – transit multicast format (n/a for head replication)
Example: { SOURCE: 0A-BC-DE / ISID: fe-dc-ba }
MMAC-DA: A3-BC-DE-FE-DC-BA 0011
:1
I=255
24
Highlighted is the routing from each member to all others.
Note the symmetry.
Unicast and multicast Follows exactly these Routes.
Multicast can be replicated at fork points or head end replicated to the uni-cast paths by configuration at edge.
ANIMATION FOR E-LAN ‘100’ WITH 7 MEMBERS
25
The Control Plane (m-in-m mode) • Industry standard IS-IS Link State Protocol is
basis for 802.1aq. • Does not require any IP to operate. • Does not preclude IPV4 or IPV6 being present in
same IS-IS instance. • SYSID carries B-MAC address • Introduces no new PDU’s to IS-IS. • Hello TLVs augmented to pass Equal Cost
Algorithm / Vid information and new NLPID. • Update TLV’s augmented to advertise SPB
specific link costs. • Update TLVs augmented to advertise ISID
information. • Update TLVs augmented to advertise nodal ‘short
form’ name SPSOURCEID (transit mcast only).
26
802.1aq ISIS LSP extensions at a glance LSPID Seq Num Checksum …. ----------------------------------------------
4455.6677.0001.00-00 0x0000007a 0xc01f ….. SOURCE 4455.6677.0001.00 HOST NAME Instance_1 NLPID SPB (0xC1) AREA ADDR 22.3344 NBR ID 4455.6677.0004.00 COST: 10 NBR ID 4455.6677.0003.00 COST: 10 SPSOURCEID 07-00-01 SPB ECT-ALGORITHM 1 ECT-VID 101 SPB ECT-ALGORITHM 0 ECT-VID 100
SPB BMAC 44-55-66-77-00-01 ECT-VID 100 SPB ISID 255T&R SPB BMAC 44-55-66-77-00-01 ECT-VID 101 SPB ISID 256T&R
10
10
255
:4
:3
LSP fragment for node :1 with 2 peers :4 and :3 and two services 255, 256
(1)
(2)
(4)
(3)
(5)
27
Loop Suppression & Avoidance Suppression
• done on the data path using an SA check. • prevents 99.99% loops if FDB’s create one. • no impact on convergence rates. • exploits symmetric/congruence properties of routing. • uses reverse learning options of most h/w to discard.
Avoidance • done by the control path • ensures no loops are ever configured in FDBs. • hellos augmented with topology ‘digests’ • mismatched digests => some forwarding entries unsafe. • blocks only ‘unsafe’ entries. • works for ALL forwarding modes current and planned.
28
802.1aq OA&M (inherited by design) Service/Network Layer – 802.1ag Connectivity Fault mgmt
•Hierarchy (honors maintenance levels/abstraction) •Continuity Check •L2 traceroute •L2 ping
Link Layer – 802.3ah •Link Monitoring (logical/physical) •Remote Failure Indication •Remote Loopback
Service Layer - Y.1731 •Multicast Loopback – depends on congruency/symmetry •Performance Measurements (Loss/Delay etc.) •One way/two way delays – symmetry important
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Recovery • ISIS augmented with multicast LSP flood to all 802.1aq
nodes. • Every 802.1aq node joins default service ISID 0xffffff. • This E-LAN is just for control plane. • LSPs can be advertised over this E-LAN • Very fast distribution protocol (h/w multicast). • On failure each end of link advertises over
this ‘default’ E-LAN (in addition to normal updates). • Reaches all 802.1aq participants at h/w multicast speed
with no CPU involvement transit. • Conceptually like having a shared LAN joining all nodes
with a physical port but no DR election etc. is done, only used as unreliable very fast distribution mechanism backed up by normal IS-IS hop by hop LSPs.
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Outline
• Challenges • What is 802.1aq/SPB • Applications • How does it work • Example (included in this deck - enjoy) • Q&A
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Outline
• Challenges • What is 802.1aq/SPB • Applications • How does it work • Example (backup slides) • Q&A (avail anytime)
AQ
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“Shortest Path Bridging – Efficient Control of Larger Ethernet Networks” : upcomming IEEE Communications Magazine – Oct 2010
“Provider Link State Bridging” : IEEE Communications Magazine V46/N9– Sept 2008 http://locuhome.com/wp-content/uploads/2009/02/ ieeecommunicationsmagazinevol46no9sep2008-carrierscaleethernet.pdf
See also the worked example – in backup slides in this deck
References
Thank-You
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EXAMPLE
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Full Transit Replication
EXAMPLE – ISIS PEERS AT NODE :3
<ottawa-9300-3>d spb The current global spb information is : Device HMAC is 44-55-66-77-00-03 Spsid is 07-00-03 Ect vlan amount is 2 Ect vlan sequence number [1] is: vlan 100 ! Ect vlan sequence number [2] is: vlan 101 ! <ottawa-9300-3>
<ottawa-9300-3>d isis peer
Peer information for ISIS(1) ---------------------------- System Id Interface Circuit Id State HoldTime Type 4455.6677.0001 Vlanif211 0000000002 Up 26s L1 4455.6677.0004 Vlanif212 0000000003 Up 23s L1 4455.6677.0005 Vlanif216 004 Up 27s L1 4455.6677.0015 Vlanif217 005 Up 27s L1 4455.6677.0017 Vlanif218 006 Up 25s L1 Total Peer(s): 5
<ottawa-9300-3>
Logging on to node :3 We can see the basic SPB info and the ISIS peers….
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EXAMPLE – LSDB at node :3 Database information for ISIS(1) -------------------------------- Level-1 Link State Database LSPID Seq Num Checksum Holdtime Length ATT/P/OL ------------------------------------------------------------------------------- 4455.6677.0001.00-00 0x00000fd2 0x1cea 1044 236 0/0/0 4455.6677.0003.00-00* 0x00001448 0x3d27 683 323 0/0/0 4455.6677.0004.00-00 0x00000ff8 0xd1d9 1090 323 0/0/0 4455.6677.0005.00-00 0x00000b3b 0x9ba7 586 317 0/0/0 4455.6677.0006.00-00 0x00000b3b 0xbc31 819 293 0/0/0 4455.6677.0007.00-00 0x00000b3b 0xce10 1075 293 0/0/0 4455.6677.0008.00-00 0x00000b3e 0xebe0 288 293 0/0/0 4455.6677.0009.00-00 0x00000b3b 0x8b77 355 317 0/0/0 4455.6677.000a.00-00 0x00000b3b 0x57a 840 294 0/0/0 4455.6677.000b.00-00 0x00000b3a 0x1665 608 294 0/0/0 4455.6677.000c.00-00 0x00000b3a 0x6903 764 294 0/0/0 4455.6677.000d.00-00 0x00000b3a 0x89fd 431 294 0/0/0 4455.6677.000e.00-00 0x00000b39 0x3445 611 294 0/0/0 4455.6677.000f.00-00 0x00000b3a 0xdabe 616 294 0/0/0 4455.6677.0010.00-00 0x00000b3b 0x810e 452 294 0/0/0 4455.6677.0011.00-00 0x00000b3a 0x1b46 645 294 0/0/0 4455.6677.0012.00-00 0x00000b39 0x1b3e 447 294 0/0/0 4455.6677.0013.00-00 0x00000b3a 0x943a 419 176 0/0/0 4455.6677.0014.00-00 0x00000b3b 0xdff2 693 176 0/0/0 4455.6677.0015.00-00 0x00000b41 0xdade 1141 508 0/0/0 4455.6677.0016.00-00 0x00000b3e 0xa832 1011 464 0/0/0 4455.6677.0017.00-00 0x00000b40 0x1563 640 508 0/0/0 4455.6677.0018.00-00 0x00000b3a 0xadee 417 464 0/0/0 4455.6677.0019.00-00 0x00000b3a 0xcff 291 158 0/0/0 4455.6677.001a.00-00 0x00000b3b 0xb131 794 176 0/0/0 4455.6677.001b.00-00 0x00000b3b 0x7062 822 176 0/0/0 4455.6677.001c.00-00 0x00000b3b 0x5876 463 176 0/0/0 4455.6677.001d.00-00 0x00000b3b 0xa610 460 176 0/0/0 4455.6677.001e.00-00 0x00000b3a 0xf5c6 627 176 0/0/0 4455.6677.001f.00-00 0x00000b3b 0x8a19 825 176 0/0/0 4455.6677.0020.00-00 0x00000b3a 0x960a 584 176 0/0/0 4455.6677.0021.00-00 0x00000b3b 0x5b58 1033 176 0/0/0 4455.6677.0022.00-00 0x00000b3a 0x8927 693 176 0/0/0 4455.6677.0023.00-00 0x00000b3b 0x9352 664 158 0/0/0 4455.6677.0024.00-00 0x00000b39 0xc8ec 736 176 0/0/0
*(In TLV)-Leaking Route, *(By LSPID)-Self LSP, +-Self LSP(Extended), ATT-Attached, P-Partition, OL-Overload
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<ottawa-9300-3>d isis lsdb 4455.6677.0001.00-00 verbose
Database information for ISIS(1) --------------------------------
Level-1 Link State Database
LSPID Seq Num Checksum Holdtime -------------------------------------------------------------
4455.6677.0001.00-00 0x00000fd3 0x1aeb 1194 SOURCE 4455.6677.0001.00 NLPID SPB(0xC1) AREA ADDR 22.3344 +NBR ID 4455.6677.0003.00 COST: 10 +NBR ID 4455.6677.0004.00 COST: 10 SPB ECT-ALGORITHM 0 ECT-VID 100 SPB ECT-ALGORITHM 1 ECT-VID 101 SPB ECT-ALGORITHM 2 ECT-VID 0 ……. SPB ECT-ALGORITHM 15 ECT-VID 0 SPSID 07-00-01 SPB BMAC 44-55-66-77-00-01 ECT-VID 100 SPB ISID 255T&R
<ottawa-9300-3>
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EXAMPLE – NODE :3 ROUTE TO :10 (first equal cost path)
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EXAMPLE – NODE :3 ROUTE TO :10 (second equal cost path)
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EXAMPLE: E-LAN MCAST ROUTES FROM :1 (left) and :26 (right)
Here are the multicast routes from node 1 for service 255 and also from node 26 for service 255. Note the symmetry in the route between the two multicast trees. The unicast route between :1 and :26 is also along that same path for the chosen B-VID. Since we’ve asked for transit replication for all members of the E-LAN we install MCAST …
SRC
SRC
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EXAMPLE: E-LAN MCAST ROUTES FROM :1 (left) and :26 (right)
<ottawa-9300-3>d spb mmac --------------------------------------------------------------- IN_PORT VID BMAC OUT_PORT --------------------------------------------------------------- ... GE2/0/11 100 7300-0100-00ff GE2/0/16, GE2/0/10 ... Total multicast num is 7 <ottawa-9300-3>
+-----+-------+-------------------+------+--------------- | FLG | IN/IF | DESTINATION ADDR | BVID | OUT/IF(s) +-----+-------+-------------------+------+--------------- | | if/01 | 7300-0100-00ff | 0100 | {if/5,if/6 } ….
5
MULTICAST ADDRESS IS: [ SOURCE = 07-00-01 | ISID=00-00-ff ]
We only get this state if we configure transmit membership in the E-LAN. Transmit still possible without multicast state but uses serial replication at head end. Operator chooses trade-off between state/bandwidth usage.
1
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Here are all mFIBs on nodes :3 and :13 related to this E-LAN.
<ottawa-9300-3>d spb mmac --------------------------------------------------------------- IN_PORT VID BMAC OUT_PORT --------------------------------------------------------------- GE2/0/16 100 0300-1300-00ff GE2/0/10, GE2/0/11 GE2/0/16 100 0300-1400-00ff GE2/0/10, GE2/0/11 GE2/0/16 100 0300-1a00-00ff GE2/0/10, GE2/0/11 GE2/0/16 100 0300-1d00-00ff GE2/0/10, GE2/0/11 GE2/0/16 100 0300-1e00-00ff GE2/0/10, GE2/0/11 GE2/0/11 100 7300-0100-00ff GE2/0/16, GE2/0/10 GE2/0/10 100 7300-0200-00ff GE2/0/16, GE2/0/11 Total multicast num is 7 <ottawa-9300-3>
+-----+-------+-------------------+------+--------------- | FLG | IN/IF | DESTINATION ADDR | BVID | OUT/IF(s) +-----+-------+-------------------+------+--------------- | | if/01 | 7300-0100-00ff | 0100 | {if/5,if/6 } | | if/01 | 7300-0200-00ff | 0100 | {if/5,if/6 } | | if/01 | 0300-1a00-00ff | 0100 | {if/5,if/6 } | | if/05 | 0300-1d00-00ff | 0100 | {if/1,if/3,if/6 } | | if/06 | 0300-1e00-00ff | 0100 | {if/1,if/3,if/5 } | | if/03 | 0300-2400-00ff | 0100 | {if/5,if/6 }
